Procedural hair deformation for rocks
Okay, I can't post any images right now.  However, it's pretty basic what I did, so let me explain real quick.  I actually got the general idea from a great YouTube tutorial author that I watch, Sardi Pax.  

I have a scene with a plane for the ground.  I put a hair particle system all across the plane.  I then went to another layer and created five ICOSphere "rocks" and applied a Noise and the Voronoi textures used for displacement mappings(set the material's settings section tab displacement flag to true after enabling "Experimental").  Then I tweaked these displacements to make the rocks look different.  I also applied a simple deform modifier with an empty to each rock to get unique shapes for them.  Then I Object grouped(CTRL+G) the rocks on that separate layer together.  Then I went back to my original layer with the plane and then used the rocks group as the hair particle system's display property.  I also created vertex groups on my plane(randomly selected).  Then I applied the rocks(with pick random from group selection in the particle's properties, so it would pick random rocks for me from the rock object group) to the plane's vertex groups that I created.  And since I put the rocks at 0 on the Z-axis on the other layer the rocks look buried in the plane's "dirt", pretty neat.   This gave me a decent spread across the plane of random rocks that didn't appear to be too repetitious.  I hope this makes sense, I'll try to post images later.